This three-year project will investigate the impact of selected managed care organization (MCO) policies on the quality of treatment and health outcomes for children with asthma. The study sites include 9 MCO plans that participate in the Maryland Medicaid HealthChoice program implemented in June 1997. Among the estimated 319,000 Medicaid recipients enrolled are approximately 4,000 children aged 5-18 diagnosed with asthma. These children are distributed statewide among the 9 plans. The MCOs vary widely in terms of policies whose effect is hypothesized either (1) to restrict access to high quality care for this population group (e.g., restricted access to specialists, formulary restrictions and limited day supply for asthma medications, failure to cover spacers, nebulizers, or peak flow meters), or (2) to enable recipients to gain better access to effective treatment (e.g. asthma disease management protocols based on NAEPP guidelines). This study has two major aims. The first is to determine the impact that transition from fee-for-service to managed care has on quality of asthma treatment as measured by adherence to NAEPP guidelines, the incidence of potentially avoidable hospitalizations and emergency room visits, and self-reported quality of life indicators specific to asthma. The second aim is to determine-given these transition effects-the impact that exposure to specific restrictive and enabling MCO policies have on pediatric asthma patients based on the same set of process and outcome indicators. The study will employ a quasi-experimental, open-cohort design with subjects selected retrospectively based on a diagnosis of asthma in the pre-MCO enrollment period and a smaller number of incident cases identified in the post-MCO period. Data for the study will come from Medicaid claims files, MCO encounter data (that mimic claims data), surveys and periodic tracking of MCO plan policies, and an asthma-specific, health-related quality of life survey of a sample of study subjects. The analysis will include (1) descriptive, longitudinal profiles of subjects' treatment patterns across plans and through the fee-for-service/MCO transition, (2) an in-depth qualitative assessment of the characteristics of restrictive and enabling MCO policies viewed from the perspective of asthma patients, their parents, and plan administrators, and (3) inferential tests of the study hypothesizes using multivariate regression analyses appropriate for open cohort designs. The findings from this study are expected to shed new light on how restrictive and enabling MCO policies affect quality of care and health outcomes for children with asthma.